【Unity3D】用继承EditorUpdater类来实现Editor模式下的后台处理

EditorWindow类的OnGUI函数只会在窗口焦点处于Editor窗口上的时候才会运行。如果希望焦点不在Editor窗口上的时候，它也能实时更新，可以实现以下方法：

但是，如果Editor窗口被贴到大窗口上后，选择和它平级的窗口，从而隐藏了Editor窗口，这样OnGUI函数仍然无法调用。所以，我们为了实现更有效的后台处理，可以采用继承一个自己写的EditorUpdate类的方式。

using System;
using System.Collections;
using System.Reflection;
using UnityEditor;
using UnityEngine;

[InitializeOnLoad]
public class EditorMonoBehaviour
{
    static EditorMonoBehaviour()
    {
        var type = Types.GetType ("UnityEditor.EditorAssemblies", "UnityEditor.dll");
        var method = type.GetMethod("SubclassesOf",BindingFlags.Static|BindingFlags.NonPublic|BindingFlags.Instance,null,new Type[]{typeof(Type)},null);
        var e = method.Invoke (null, new object[] { typeof(EditorMonoBehaviour) }) as IEnumerable;
        foreach (Type editorMonoBehaviourClass in e)
        {
            method = editorMonoBehaviourClass.BaseType.GetMethod ("OnEditorMonoBehaviour", BindingFlags.NonPublic | BindingFlags.Instance);
            if (method != null)
            {
                method.Invoke (System.Activator.CreateInstance (editorMonoBehaviourClass), new object[0]);
            }
        }
    }

    private void OnEditorMonoBehaviour()
    {
        EditorApplication.update += Update;
        EditorApplication.hierarchyWindowChanged += OnHierarchyWindowChanged;
        EditorApplication.hierarchyWindowItemOnGUI += HierarchyWindowItemOnGUI;
        EditorApplication.projectWindowChanged += OnProjectWindowChanged;
        EditorApplication.projectWindowItemOnGUI += ProjectWindowItemOnGUI;
        EditorApplication.modifierKeysChanged += OnModifierKeysChanged;

        EditorApplication.CallbackFunction function = () => OnGlobalEventHandler (Event.current);
        FieldInfo info = typeof(EditorApplication).GetField ("globalEventHandler", BindingFlags.Static | BindingFlags.Instance | BindingFlags.NonPublic);
        EditorApplication.CallbackFunction functions = (EditorApplication.CallbackFunction)info.GetValue (null);
        function += function;
        info.SetValue (null, (object)functions);
        EditorApplication.searchChanged += OnSearchChanged;
        EditorApplication.playmodeStateChanged += () => {
            if(EditorApplication.isPaused)
            {
                OnPlaymodeStateChanged(PlayModeState.Paused);
            }
            if(EditorApplication.isPlaying)
            {
                OnPlaymodeStateChanged(PlayModeState.Playing);
            }
            if(EditorApplication.isPlayingOrWillChangePlaymode)
            {
                OnPlaymodeStateChanged(PlayModeState.PlayingOrWillChangePlayMode);
            }
        };

        Start ();
    }

    public virtual void Start()
    {}

    public virtual void Update()
    {}

    public virtual void OnHierarchyWindowChanged()
    {}

    public virtual void HierarchyWindowItemOnGUI(int instanceID,Rect selectionRect)
    {}

    public virtual void OnProjectWindowChanged()
    {}

    public virtual void ProjectWindowItemOnGUI(string guid,Rect selectionRect)
    {}

    public virtual void OnModifierKeysChanged()
    {}

    public virtual void OnGlobalEventHandler(Event e)
    {}

    public virtual void OnSearchChanged()
    {}

    public virtual void OnPlaymodeStateChanged(PlayModeState playModeState)
    {}

    public enum PlayModeState
    {
        Playing,
        Paused,
        Stop,
        PlayingOrWillChangePlayMode
    }
}

然后在另一个脚本中继承这个类，并重载Start和Update等方法，在这些方法中实现后台逻辑，就可以后台更新了。

using UnityEngine;
using System.Collections;

public class UpdaterTest :EditorMonoBehaviour
{
    public override void Update ()
    {

    }
}